Conventional high power semiconductor packages with a semiconductor die (chip) require a relatively large PCB (printed circuit board) footprint. Both main surfaces of the die typically have one or more electrodes. The die is attached to a PCB with one main surface facing the PCB and the other main surface facing away from the PCB. Each electrode disposed at the facing surface of the die is attached to a corresponding electrically conductive region of the PCB e.g. in a source-down or drain-down configuration. Metal clips or other connecting elements such as bonding wires or ribbons extend from the PCB to the other main surface of the die to make electrical connection with each electrode disposed at the surface of the die facing away from the PCB. Many ‘squares’ (i.e. 1 mm square units) are required on the surface of the PCB to accommodate such a source-down or drain-down package configuration, increasing the cost of the package. In addition, heat expelled at the main surface of the die facing the substrate is at least partly dissipated through the PCB/substrate. Conventional PCBs therefore must provide both an electrical and thermal path for components mounted on the PCB, resulting in a high number of components sharing the designed thermal paths of the PCB.